Of the 112 polished granite panels of the Marine Corps War Memorial monuments base, 28 have loosened and slipped.
It appears that the horizontal panels were not set with vertical bronze pins anchored to concrete deck as noted on the original design drawings. Instead the horizontal panels were poorly secured at the top edge two adjacent horizontal panels with horizontal bronze pins through bronze anchor straps fully set and motor not concrete and failing.the slightly inclined horizontal panels are poorly fastened and slipping outward.
Similarly the vertical panels were not secured and cavity with bronze Lewis ( dovetail ) stone anchors as noted on original design drawings. Instead it appears that the vertical panels were secured with a single bronze pin at center point to bronze anchor straps fastened with two corroded steel bolts seven lead shields into concrete deck the single center pin acted as a pivot point alone horizontal rotation/displacement about a probable single metal pin at base. The steel bolts were set to close to to edge popping concrete , and had rusted through; anchor straps were easily removed by hand.
Continued gradual slippage of the horizontal panels would likely override the vertical panels, but sudden slippage triggered by an earthquake or tremor could topple the vertical panels.
NOTE: Several earthquakes have occurred within a 25 mile radius of the Marine Corps War Memorial since 1997, the most recent Northwest of Rockville, Maryland measuring a 3.5 on the Richter scale.
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